The Hall effect occurs when a conductor carrying current is placed in a magnetic field. A voltage is generated according to the cross product of the field and flow of current. Sensors operating on the Hall effect can be modeled like a Wheatstone bridge. Multiple sensors may be used in parallel, and are typically coupled to a differential amplifier to measure the generated voltage. To reduce current, several different implementations of bridges have been used, including thin conducting layers, commutation of a single bridge, or modifying the duty cycle of the bridges. These arrangements increase the complexity and cost of the sensor.